Many food products are aerated, such as mousses, ice cream, and whipped cream. These food products contain small gas bubbles, and the gases may include air, nitrogen, and/or carbon dioxide. Aerated food products are being developed with two aspects which are of importance: first the foamability (how easy is it to aerate the food product), and second the stability of the aeration during storage (how well do the air bubbles remain intact upon storage of the aerated food product).
Water-in-oil emulsions like spreads, butter and margarine, may contain air bubbles, in order to reduce the caloric content of the product and/or to provide a product with an attractive structure.
Whipped butter is generally made by whipping air into softened butter at slightly elevated temperatures, and then cooling it. U.S. Pat. No. 2,937,093 discloses a process for manufacturing whipped margarine. This process comprises combining liquid margarine with an inert gas (e.g. nitrogen), cooling the mixture, agitating the cooled mixture under pressure to produce a flowable mass, and then releasing the pressure.
EP 285 198 A2 discloses food products such as margarine or shortening comprising a continuous fat phase and a dispersed gas phase, which exhibit an improved spattering behaviour when used for frying. The product is produced on a votator line and the gas is incorporated in the composition near the beginning of the line, while the composition still comprises essentially no crystallized fat.
The use of sucrose fatty acid esters in fat-continuous emulsions is known.
EP 1 052 284 A1 claims a setting agent of fats and oils containing sucrose fatty acid ester with a HLB smaller than 3, and mentions margarine and fat spreads that may contain the mixture of fat and sucrose fatty acid ester. The setting agent is used to modify the hardness of the oil phase.
EP 375 238 A2 discloses aerated fatty composition containing at least 5 wt %, preferably 20 wt % to 55 wt % of sugar fatty acid ester. The other part of the fatty composition is optionally fatty materials like triglycerides, lipid soluble flavours, emulsifiers, and colourants. The compositions are in the form of shortenings, hence free from water. The examples disclose sucrose octa-esters and sucrose hepta-esters. The fatty composition may be used as a table spread, albeit not in the form of an emulsion, but as a water-free spread.
EP 410 507 A2 discloses polyol fatty acid polyesters for use in aerated fat continuous products. The fat blend of the continuous phase comprises at least 50% of the polyol fatty acid polyesters. A preferred polyol is sucrose. The fat compositions may be used in chocolate-like food products.
WO 2010/112835 A2 discloses aerated oil continuous emulsion containing an emulsifier with HLB value less than 8, preferably 2 to 7, more preferred 4 to 6. The emulsifier may be a sucrose ester. The aerated emulsion is made by first mixing the oil and water phases, followed by aerating the emulsion. The gas bubbles may be located in the fat phase of the emulsion, and the walls of the gas bubbles may be formed from fat phase material.
US 2006/0078659 A1 discloses a mousse-type spread comprising a water-in-oil type emulsion, that may contain sucrose fatty acid ester as emulsifier (with HLB value less than 7, preferably less than 5). The mousse is formed when the emulsion is discharged from a nozzle under pressure.
WO 00/38546 discloses an aerated water-in-oil emulsion, wherein the aqueous phase is aerated using a sucrose ester with a HLB value of 16, before it is mixed with a continuous oil phase. The size of the air bubbles is preferably between 0.5 and 25 micrometer, more preferred between 1 and 5 micrometer.
Similarly, WO 94/12063 describes aerated emulsions, that may be in the form of water-in-oil or oil-in-water emulsions. Mono-, di- or tri-longchain fatty acid esters of sucrose are used, e.g. sucrose monostearate ester. The gas bubbles are prepared in the aqueous phase first, before being mixed with the oil phase.
Sucrose fatty acid esters have also been described in aerated oil-in-water emulsions, e.g. in EP 2 042 154 A1, DE 697 23 027 T2, JP 2006-304665, WO 2004/041002 A1, and WO 2008/110502 A1.